1. Field
Embodiments relate to a secondary battery.
2. Description of the Related Art
Secondary batteries are rechargeable, unlike primary batteries which are not. Types of secondary batteries include a low capacity battery including a battery cell in the form of a pack and typically used for small portable electronic devices, e.g., cellular phones and camcorders, and a high capacity battery including dozens of battery cells connected to one another and widely used as a motor-driving power source for electric scooters, hybrid vehicles, or electric vehicles.
Secondary batteries may be manufactured in various shapes, including cylindrical and prismatic shapes. Each of the unit batteries typically includes an electrode assembly having a positive electrode, a negative electrode, and a separator between the positive and negative electrodes, a case for housing the electrode assembly together with an electrolyte, and a cap assembly installed to seal the case and having electrode terminals.
If excessive heat is generated or the internal pressure of the secondary battery increases due to a variety of factors, e.g., decomposition of an electrolyte, ignition or explosion of the secondary battery may result. Accordingly, there is a need for a secondary battery having improved safety.